Electric igniter.



m1. KRANNICHFELDT.

ELECTR'IC IGNITER.

APPLICATION FILED JUNE-20. I914. 1,263,256. Patented Apr. 16, 1918.

2 SHEETS-SHEET I.

WIT/V5555 J. KRANNICHFELDT.

ELECTRIC IGNITER.

APPLICATION FILED JUNE 20. 1914.

I 1,263,256. Patented Apr. 16, 1918.

2 SHEETS-SHEET 2- WIT/$555 f? I wkg/ vjimj m;

UNITED STATES PATENT OFFICE.

J'OHANN KRANNICHFELDT, 0F COLOGNE-NIEHL-ON-THE-RHINE, GERMANY.

ELECTRIC IGNITEB.

To all whom it may concern:

Be it known that I, JOHANN KRANNICH- F anna, a subject of the King of Prussia,residlng at Cologne-Niehl-on-the-Rhine, in the Kmgdorn of Prussia and German Empire, have invented new and useful Improvements n Electric Igniters, of which the following is a specification.

The present invention relates to an improvedelectric igniter, which has several advantages over existing devices of the kind. On the accompanying drawing, which lllustrates the invention by Way of example, several constructions of the igniter are shown.

Figures 1 and 2 show in longitudinal section one construction in which the insulator carrying the igniting wire is fastened in the tube containing the explosive by a short sleeve in combination with a sulfur casting or the like.

Figs. 3 and 4 represent an igniter in which theinsulator is held by a collar.

Fig. 5 shows a similar igniter to that shown in Figs. 3 and 4, but the explosive plug closing one end of the tube containing the charge has a' smaller diameter.

Fig. 6 shows a further modification in regard to the manner of securing the plug in the tube.

Fig. 7 represents the incandescence wire in an inclined osition. I

Fig. 8 is a iew corresponding to Fig. 3', but showing the plug carried by the outside sleeve of the igniter.

Figs. 9 and 10 represent another way of fastening the insulatin body which carries the incandescence wire 1n the sleeve.

Figs. 11, 12 and 13, 14 show further constructions of the device for holding the insulator.

Figs. 15 and 16.show another arrangement of the pole pieces on the insulator.

The insulator a (Figs. 1 and 2) has a 0011- ducting layer 6, 0 on each side or surround- I ing each edge (Figs. 15 and 16) and is cut out at the top so as to present a forked shape, the prongs d, e of said fork being bridged by the wire f, which is in contact with the conductive layer 6 of the prong d and with the conductive layer 0 of the prong e. The electric current is led to the layers In and c by the wires 9, It, so that the wire f can be rendered incandescent. 'The insulator a is secured in the tube z'by the sleeve 7:, in which said insulator is fastened by a casting Z of Specification of Letters Patent.

Patented Apr. 16, 1918.

Application filed June 20, 1914. Serial No. 846,351.

sulfur or of some other suitable substance. For the purpose of better securing said insulator a in the sleeve is, the former can be cut out at m and the recess or notch thus formed will be filledout by the casting Z. The wire f is surrounded by a combustive n of slowly burning and weakly igniting property, and the top of the tube '5 is closed by the plug 0, which consists of a combustlve of quick burning pro erty.

Any suitable com ust'ives having these properties may be employed, for example, potassium nitrate, charcoal and sulfur, w th a suitable binder may be used for the quick burning combustive, and the same ingredients mixed with an inert substance as chalk, clay, etc., may be used for the slow burning combustive.

The igniter shown in Figs. 3 and4 differs from that shown in Figs. 1 and 2 by the 111- sulator a being secured in the tube 71 by a collar is, which prevents the cast sulfur Z from penetrating to the charge n. A further difi'erence of this construction consists in the fact that the diameter of the plug 0 is reduced by an intercepted sleeve q. Tl'llS igniter is provided with an outer tube u in which it is held by the casting Z. In this tubeu the plug 0 can be inserted, as shown in Fig. 8, instead of into the tube 71.

In Figs. 5 and 6 igniters are shown WhlCll only differ from those shown in Figs. 3 and 4 by the fact that in Fig. 5 the plug ohas a still further reduced diameter and fits into a central hole provided at the end of the tube 13, while in Fig. 6 the plug 0 has a diameter as large as the interior of the tube z and is retained in said sleeve by a flange 7.

According to Figs. 9 and 10 the insulator is held in the tube 71 by two collars k, 7;, which are provided with a slot on opposlte sides (Fig. 10) into which the insulator fits. When these collars are inserted into the tube 5, they hold the insulator between them.

Figs. 11 and 12 show two v1ews, at right angles to each other, of an lnsulator which is provided with a hole, through which a tongue v provided on the collar piece 70 of semi-circular section passes, said tongue fittin into a hole to of a second sem -clrcular col ar piece 77. By this means both collar pieces k, k are united together and hold the insulator between them.

The construction shown in Figs. 13 and 14 differs from that shown in Figs. 11 and 12 only by the fact that the tongue does not fit into a hole in-the other collar piece, but fits into a groove 10 in said other collar piece. 'over that shown ,inFigs. 11 and 12 consists in the fact that the collar pieces with tongue and groove can be made in long strips from whichthe separate pieces are cut, it only being necessary to cut oil the ends of the tongue, so as to fit into the hole in the insulator. a

lgniters of the kind above described have, firstly, the advantage that the igniting wire f, owing to the fork shape of the end of the o 15 insulator a, provided with a conductive layer 12, c on each side, has a considerable length, and is, accordingly, more effective, because the'hea-t conducted. away by the metal layers forming the poles is less detrimental. Moreover the length of said wire is quite uniform,

- because the distance between the prongs d,

' e is always the same. The described manner of attaching the igniting wire has the further advantage that in'constructing the igniters the insulatorsamay be fastened in a suitable device with their top ends close together, whereupon the wire f can be attached with but extremely little waste to the'conductive layers 19, 0. In order to stillfurther increase the length of the wire f the prongs v d, 0 may be of different-length, so that the wire f takes an, inclined position, as shown in Fig. 7. A further important advantage of this igniter consists in the ability of oh- ;5 taining a combined or aggregate operation of any number of such igniters electrically connected in series, although constructed for practically momentary ignition. This result is obtained by using the slowly burning to charge 1 in combination with the plug o of a .quickburning character. When the charge 0?. has been ignited by the incandescence of the wire I", the. plug 0 serves at first .to isolate the combustion, thus to prevent L5 said combustion from extendin to the explosive s (Fig. 1), until said p ug is itself ignited, whereupon a flame i's'produced and caused to. act on the charge 8, which is contained in a tube t adapted to be pushed over 0"the tube 2'. r 1

What I claim'and desire tosecure by Let- .ters Patent of the United States is 1. An electric igniter comprising in combination a flat insulating body out out to 5 form a fork shaped end, a layer of electrically conducting material on each side of said body and the prongs of the fork shaped endand on each face of said body, and forming poles.

0 2. An electric igniter-comprising in combination an insulating body cut out to form a fork shaped end, and a layer of electrically conducting material embracing a portion of The advantage of this construction both faces of the body, at each side thereof, and the prongs of the fork shaped arms, and forming poles.

3. An electric igniter, comprising in 'combination, a flat insulating body cutout to form a fork shaped end, a layer of electrically conductive material embracing a portlon of each flat surface thereof on each side of said body, and the prongs of the forkshaped end, a wire bridging the prongs of said insulating body and the metal layers on said body, a tube inclosing said insulating body, and means for holding the insulating body in place, substantially as, and for the purpose, set forth.

4. An electric igniter, comprising in combination an insulating body having a fork shape at one end, electrically conductive. layers on said insulating body, a wire bridging the prongs and conductive layers, a tube inclosmg the insulating body, means held in said tube and engaging the said insulating body to hold the same in place, a slowly burning explosive in said tube and in contact with the wire, and a plug of a quick burning explosive in contact with the slow burning explosive and closing the end of the tube.

5. The described electric igniter which comprises an insulating body having a fork shape at one end, electrically conductive layers on said insulating body, a wire bridging the prongs and conductive layers of said insulating body, a tube, a body surrounding said insulating body and fitting into said tube, a-casting fixing said body surrounding said insulating body in said tube, a slowly burning explosive in said tube and in contact with said wire, and a plug of a quick burnin explosive closingthe end of said tube, su 'stantially as, and for the purpose, set forth. I 6. An electric igniter, comprising incom- 'bin'ation, an insulating body having a hole' between its two ends, layers of electrically conductin material on said body,- a wire bridging t e rongs of said insulating body and the meta layers on said body, a collar piece of about semi-circular section having a tongue adapted to roject through the hole in said insulating bo y and betweenthe conductive layers, and a second collar piece having an opening to receive said tongue, and

a tube fittin over said collar pieces and insulating b0 y, substantially as set forth.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

JON KRANNICHFELDT. I

Witnesses: I

OsoAn Go'rrsomnn, LOUIS 'VAND RY. 

